Field of the Invention
The invention relates to a nanorod and a manufacturing method thereof, and more particularly relates to an indium oxide nanorod and a manufacturing method thereof.
Description of Related Art
With the rapid progress of science and technology, areas such as electronics, material, physics, chemistry, and biology have evolved from the Micron Era into the so-called Nano Era. When the device size is miniaturized to the nano-level, the physical, mechanical and chemical properties of the device differ from those when the device is still a block material. Therefore, in addition to changing the composition of the material to obtain required properties of different materials, basic characteristics such as the melting point, color, and optical, electrical, and magnetic properties of the same material may also be manipulated by controlling the size and shape of the material. High-performance products or techniques that cannot be achieved in the past may now be realized in the field of nano science and technology.
Generally, there are many types of nanomaterials, including metal, metal oxide, semiconductor, ceramics, polymer material, etc. In addition, nanostructures may be divided into one-dimensional, two-dimensional, and three-dimensional nanostructures according to different shapes, sizes, and distribution ranges. The current mechanisms for growth of nanostructures (e.g., nanorods) mainly include a vapor-liquid-solid (VLS) growth mechanism and a vapor-solid (VS) growth mechanism. According to the VLS growth mechanism, the vapor-phase reactant is attached to the metal catalyst to form a liquid alloy at the eutectic temperature. In the case where the material of the reactant is a semiconductor material, when the semiconductor material in the metal-semiconductor alloy is supersaturated, the semiconductor is precipitated from the bottom of the metal catalyst, and the precipitated semiconductor material pushes the metal catalyst up and thereby forms the nanorods having directionality. As compared with the VLS growth mechanism, the vapor-solid (VS) growth mechanism can grow nanostructures without the metal catalyst. However, due to the absence of the metal catalyst that can absorb the reactant and serve as the nucleation site, the nanostructures grown by the VS growth mechanism do not have directionality and require longer formation time (about 1 hour or more). Thus, how to efficiently manufacturing nanostructures having directionality without configuration of the metal catalyst is an issue that needs to be addressed.